JP3463993B2 - Airbag device for side collision - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a side collision airbag apparatus, and more particularly, to a side collision airbag apparatus capable of efficiently using inflation energy. 2. Description of the Related Art In an automobile, a restraint device (airbag device) is used to protect the body of an occupant therein. Vehicle restraint systems include a front restraint device that physically restrains the occupant's body during a frontal collision to protect the occupant, and a side restraint device that physically restrains the occupant's body during a side collision to protect the occupant. Devices are known. A side restraint device for protecting the occupant is provided to protect the center pillar or door and the occupant's body, especially the chest. The side restraint device, as shown in FIGS.
A base end portion is fixed to a side portion 101 of the seat body, and a bag 102 is provided which is instantaneously inflated and extended by gas inflation of an inflator 103 at the time of a side collision. The bag deployed in this manner enters between the side region of the occupant's upper body and the side inner surface 104 of the vehicle body to protect the occupant's body. [0003] In such a side restraint device, the inflation acceleration is large in the inflation state at the initial stage of inflation, and the inflation acceleration rapidly decreases at the stage where the body receives the protection force from the bag. desirable. Such a restraining device can be implemented as a perforated surface of the inflation surface of the bag, but the perforated hole may be damaged upon inflation. Japanese Patent Application Laid-Open No. H8-2682 discloses a bag in which the periphery of the hole is reinforced so as not to cause such a fear.
No. 13. The document further discloses a bag in which a protruding portion whose protruding end face is open is formed, and the reinforcing effect is obtained by forming the protruding portion.
The document further discloses a restraining device in which such a protrusion is turned over and the protrusion enters the interior space of the bag. Such a known device is excellent in that it is quickly deployed in the early stage of inflation, degassed in the last stage of inflation, and has an excellent reinforcing effect around the hole. [0004] Rapid expansion is maintained until the initial stage of expansion or effective expansion, and after the end of expansion or after effective expansion, degassing is more appropriate, and the shape design ensures the appropriateness. It is desired. SUMMARY OF THE INVENTION An object of the present invention is to maintain rapid expansion at the initial stage of expansion or until effective expansion, and degassing is more appropriate after the expansion cycle or after effective expansion. It is another object of the present invention to provide a side collision airbag device capable of ensuring its appropriateness by shape design. [0006] Means for solving the problem are expressed as follows. The technical items appearing in the expression are appended with numbers, symbols, and the like in parentheses (). The numbers, symbols, and the like are technical items that constitute at least one embodiment or a plurality of the embodiments of the present invention, in particular, the embodiments or the examples. Corresponds to the reference numerals, reference symbols, and the like assigned to the technical matters expressed in the drawings corresponding to the above. Such reference numbers and reference symbols clarify the correspondence and bridging between the technical matters described in the claims and the technical matters of the embodiments or examples. Such correspondence / bridge does not mean that the technical matters described in the claims are interpreted as being limited to the technical matters of the embodiments or the examples. The airbag device for side collision according to the present invention responds to a signal from the acceleration sensor for side collision when the vehicle collides, and the inflator (2) accommodated in the bag module disposed in the seat (3). ) Is a side airbag device for restraining an occupant by deploying the bag (1) by igniting the airbag. Such a bag (1) is provided with a protrusion (4). Openings (5, 5) are formed at both ends of the protrusion (4). When the bag (1) is folded, the protruding portion (4) enters the inside of the bag (1). [0008] The gas flow in the direction of the expansion axis (L), which strikes the back surface of the protruding portion (4), is forcibly changed in the flow path in a direction orthogonal to the direction of the expansion axis (L), and moves toward the direction of the expansion axis (L). The gas flow is rapidly decelerated at the beginning of expansion, and the flow rate of gas flowing out of the openings (5, 5) located at both end faces of the projection (4) is greatly reduced. The protrusions (4) that enter the interior of the bag (1) can be partially (locally) turned over during their entry, together with their surrounding neighborhood (FIG. 8). Such inversion can effectively prevent gas leakage at the beginning of expansion. Since the openings (5, 5) are provided on both sides, in particular since they are arranged symmetrically with respect to the inflation axis (L), the inflatable bag (1)
Can be deployed with its center line substantially coincident with the expansion axis (L). By designing the length of the protrusion in the direction perpendicular to the inflation axis direction (L) and the flow path cross-sectional area of the openings (5, 5), the speed of inflation and deployment of the bag (1), the amount of gas leakage The degree of inflation can be effectively controlled separately for the initial stage of expansion, the middle stage of expansion, and the end of expansion. Since the ejection of the gas flow in the inflation direction (L) limits the ejection of the gas flow in the inflation direction (L), a decrease in the inflation speed of the bag (1) is suppressed. FIG. 1 is a side view of an airbag apparatus for side collision according to the present invention, in which a bag is provided in a bag module together with an inflator on the side of a seat (seat cover). The bag 1 is, as shown in FIG.
Manufactured by sewing two base cloths, inflators 2 and 1
It consists of pairs. The pair is arranged and supported on the seat side portion 3. The gas discharge port of the inflator 2 that instantaneously generates high-pressure gas by the operation of an acceleration sensor (not shown) that detects the acceleration in the side direction is connected to the gas inlet of a bag formed by sewing the base cloth. I have. The bag 1 before operation is folded to have a small volume. It is preferable that the bag 1 is covered with a covering cloth that can be easily broken by the pressure due to the inflation. When the bag 1 is effectively inflated, the bag 1 is inflated into a shape as shown in FIG. 2, and the form of the inflation process and the form of the last stage of inflation are defined by a combination of a plurality of base cloths defined by sewing. The high-pressure gas discharged from the gas discharge port of the inflator 2 enters the folded bag 1, and the folded state of the bag 1 that receives the supply of such high-pressure gas to the internal space is instantaneously released. It expands and expands / expands in a substantially constant direction (expansion axis direction L) as shown in FIG. The vertical plane including the expansion axis direction L is
It is located between the occupant and the side surface of the vehicle body, in particular, between the center pillar or the window glass of the front door, and has an expansion axis
Is diagonally upward from the right, or as shown in FIGS. 2 and 3,
It faces diagonally left and upward. As shown in FIG. 4, the bag 1 is formed of a bag main body and a projection 4. The bag body portion and the protruding portion 4 can be integrally formed by sewing two base cloths by sewing. On the bag 1 after inflation, a protruding portion 4 is formed on the side of the inflation distal end surface 6 so as to project in the inflation axis direction L with respect to the inflation distal end surface 6. The protruding portion 4 has a semi-cylindrical shape, and has a cylindrical portion substantially orthogonal to the expansion axis direction L. The axis L ′ of the protrusion 4 is substantially perpendicular to the expansion axis direction L. The protruding portion 4 is open on both sides facing the direction of the axis L ′, and forms an exhaust port 5 on both sides. Before the expansion, as shown in FIG. 5, the protrusion 4 is pushed as it is in the direction opposite to the direction of the expansion axis. The protruding portions 4 are formed on both side panels, which are both side forming portions forming the bag 1 (inside forming portions forming side surfaces closer to the occupant and outer forming portions forming side surfaces farther from the occupant in FIG. 3). It is pushed in so that it can enter between. The bag 1 shown in FIG. 5 is folded so as to be folded along a plurality of folding lines a, b, and c to reduce the area, and can be stored in the seat side portion 3 as shown in FIG. . FIGS. 6 (a), 6 (b) and 6 (c) show the inflation / deployment process of the bag 1 folded as described above, and particularly show the late stage of the inflation process. The internal inflation gas starts from the one-point region, and arrows a1, a2, a3
As shown in the figure, the gas is emitted radially. The inflation flow indicated by the arrow a abuts on the ceiling surface 8 of the protrusion 4 to form a flow b along the flow, and flows out from the outlets 5 at both ends of the protrusion 4 to the outside of the bag 1. Such a jet gas hits the ceiling surface 8 to limit the jetting momentum. Even after the gas ejected from the exhaust port 5 is ejected from the exhaust port 5, the flow of the gas is subjected to resistance on the surface of the bag 1, and the ejection flow rate is limited. Such a restriction is strong at the start of expansion, weak at the end of expansion shown in FIG. 6B, and weakest at the end of expansion shown in FIG. 6C. At the time shown in FIG. 6 (c), the human body is pressing on the above-mentioned both side panels, the ejection volume of the ejection stream having reduced ejection resistance is large, and the internal pressure of the bag 1 is in the initial stage and the middle stage of the inflation. Is weaker than that of FIG. 7 shows another embodiment of the side collision airbag apparatus according to the present invention. The point that the protrusion 4 ′ is provided is the same as the above-described embodiment, but the exhaust port 5 ′ is not formed in the entire area of both ends of the protrusion 4 ′. The exhaust ports 5 ′ are formed at a plurality of locations (for example, two locations) in the root region of the protrusion 4 ′. The point that the gas flow in the expansion axis direction L is decelerated by the protrusion 4 ′, changed in the orthogonal direction c perpendicular to the expansion axis direction L, and flows out is the same as in the above-described embodiment. FIG. 8 shows still another embodiment of the side collision airbag apparatus according to the present invention. The bag 1 of the present embodiment has a shape in which the protrusion 4 shown in FIG. 5 is further pushed in the direction opposite to the inflation axis direction L, and the protrusion 4 is turned upside down. If there is one exhaust port 5, such an inversion is possible. In the present embodiment, the projection 4 is deformed flat by the pressure of the gas in the internal space of the bag 1 at the initial stage of inflation, and the exhaust port 5 is closed. The amount of gas flowing out from the protruding portion 4 in which the exhaust port 5 is closed is greatly restricted, and the expansion speed at the initial stage of expansion is faster than that of the embodiment of FIG. In the later stage of the expansion, the protrusion 4 is pushed by the internal pressure and is pushed out in the direction of the expansion axis L. In the process of being pushed out in the direction of the expansion axis L, the projecting portion 4 is again subjected to the upside down operation in the reverse direction.
The same process as the above-described expansion process shown in (a), (b), and (c) is followed. According to the airbag device for side collision according to the present invention, the restraint of the inflation shape during the inflation process is systematically defined, and both the rapid inflation at the beginning and the exhaustability at the end of inflation are improved. It can be exerted in a planned manner, and as a result, the expansion energy can be used efficiently.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an oblique projection view showing an embodiment of a side collision airbag device according to the present invention. FIG. 2 is an oblique projection view showing the change of FIG. 1; FIG. 3 is a plan view of FIG. 2; FIG. 4 is an oblique projection view showing the bag at the end of inflation. FIG. 5 is a cross-sectional view showing the bag before folding. FIGS. 6 (a), 6 (b) and 6 (c) are cross-sectional views respectively showing a process of inflating and deploying a bag. FIG. 7 is a front view showing another embodiment of the side collision airbag device according to the present invention. FIG. 8 is a front sectional view showing still another embodiment of the side collision airbag device according to the present invention. FIG. 9 is an oblique projection view showing a known vehicle side restraint device. FIG. 10 is a plan sectional view of a part of FIG. 9; [Description of Signs] 1 ... Bag 2 ... Inflator 4 ... Protrusion 5 ... Opening

Continuation of front page (56) References JP-A-9-315245 (JP, A) JP-A-9-272394 (JP, A) JP-A-10-338097 (JP, A) JP-A-51-20334 (JP) JP-A-4-306147 (JP, A) JP-A-6-1188 (JP, A) JP-A-8-268213 (JP, A) JP-A-49-116743 (JP, U) (58) Field surveyed (Int.Cl. ⁷ , DB name) B60R 21/22

Claims (1)

(57) Claims: At the time of a vehicle collision, an inflator housed in a bag module arranged in a seat is ignited in response to a signal from a side collision acceleration sensor. In the side airbag device for deploying the bag and restraining an occupant, in the case where the bag is provided with a protruding portion and openings are formed at both ends of the protruding portion to fold the bag,
The protrusion is found not enter the interior of the bag, upon inflation of said bag, abutting the rear surface of the projecting portion
The flow path from the expansion direction to the direction substantially perpendicular to the expansion direction.
The gas flow to be discharged is exhausted from the opening .